Computer resource requirements for commercial and government applications often fluctuate over time. For instance, a business may experience periods of peak activity that exceed comparable processing or memory requirements of other periods. In another scenario, sporadic or unexpected sales or employee growth may similarly burden existing computing resources with increased requirements. When faced with these increased resource demands, a user would conventionally have to purchase new hardware resources capable of accommodating the elevated computing needs. Such purchase requirements can represent a major, if not preclusive, expenditure for a user, who may have insufficient capital or time to react to rapid growth requirements.
To this end, computing architectures such as the power on demand (POD) design, developed by International Business Machines Corporation, allow customers to effectively rent resources such as processors on an as-needed basis. More particularly, a customer may temporarily enable standby processors that are initially dormant within their machine. Where desired, the standby processors are not included in the up front, baseline cost of the machine. As such, for a relatively smaller initial capital investment, a customer may activate and deactivate standby processors as needed for a fee.
Another type of power on demand design utilizes complete computer systems as standby resources. For example, in high availability systems, it may be desirable to utilize data mirroring, where the memory of a backup computer system is made to mirror the memory of a primary computer system. That is, the same updates made to the data on the primary system are made to the backup system. For instance, write input/output (I/O) requests executed in the memory of the primary computer system are also transmitted to the backup computer system for execution in the backup memory. In the event that the primary computer system experiences a failure or sequence of failures leading to a crash, the user ideally becomes connected to the backup computer system through the high availability network and continues operation at the same point using the backup computer data. Thus, the user can theoretically access the same files through the backup computer system on the backup memory as the user could previously access in the primary system.
In the context of capacity on demand, a standby resource may comprise such a backup system. That is, a resource that includes a network, computer, processor, memory or other computer asset may temporarily activate to mirror data in place of or otherwise compensate for a corresponding failed resource. In this manner, such selective utilization of standby resources provides customers with another layer of optimized access and usage. Conversely, capacity on demand systems supply system providers with a creative way to satisfy customer performance and cost requirements, while additionally providing an increased revenue source.
To this end, customer use of the standby resources must be monitored for billing and other accountability purposes. However, current billing practices require the payment of certain license and hardware fees related to the upkeep and management of standby resources, regardless of whether the resources are ever actually used in their backup capacity. Moreover, current billing practices make no allowance for the cause of the standby resource activation. For instance, a customer may be billed the same rate for standby resource usage irrespective of whether the standby resource was activated in response to an ordinary customer requirement or a provider problem. A sense of fairness and good business sense suggests that a customer who had to activate a standby resource because of ineffective code supplied by the provider should be entitled to a discounted rate.
Consequently, supervisory mechanisms are needed so that the billing company can properly account for the cause of standby resource usage. It may be desired, for example, to charge a higher fee for standby resources activated in the course of ordinary business than for those used in response to a provider error. There is thus a need for an improved manner of charging a customer for standby resource usage.